The present invention relates to an image forming apparatus including a photoconductive drum or belt or similar image carrier and more particularly to a developing device included in an image forming apparatus for causing a developing liquid in the form of a thin layer to contact and develop a latent image electrostatically formed on an image carrier.
It is a common practice with a developing device of the type described to use an applicator roller for applying a developing liquid to an image carrier in the form of a thin uniform layer. However, the conventional liquid application using an applicator roller has the following problems left unsolved. At the outlet of a nip where the applicator roller and a developer carrier contact each other, the developing liquid between the roller and the carrier is separated into a layer left on the roller and a layer transferred to the carrier. At this instant, cavitation occurs on the surfaces of such layers and brings about fine irregularities including spot-like voids and stripe-like ribs extending in the direction of movement of the developer carrier. The fine irregularities lower image quality. Further, if the developing liquid is not applied to the developer carrier in a constant amount, then the resulting image density is irregular.